Abstract

Percutaneous valve implantations allow treatment of heart valve dysfunctions by a minimally invasive approach. This intervention has revolutionised the field of interventional cardiology over the last decade. There is an alternative to open heart surgery for each cardiac valve. However, the widespread use of these techniques is still limited to a relatively small percentage of patients who are morphologically and functionally suitable for the currently available devices. Patient-specific finite element analyses are an engineering tool that include three-dimensional reconstruction of patient-specific anatomies in the form of a numerical model. In this scenario, it is possible to realistically simulate the outcome of a procedure and the performance of specific devices in silico (on the computer) and supplement in vitro tests. In this thesis, analyses of this kind have been applied for simulating transcatheter valve implantation in specific cases. First, a study on a novel device for percutaneous pulmonary valve implantation (PPVI) was used to support the treatment of the first selected patient. Second, the feasibility of this novel procedure was tested on a large patient population in order to quantify the impact of introducing this innovation. Finally, this computational model has been applied on a more complex scenario: the application of an existing device (transcatheter aortic valve implantation – TAVI) in a group of patients currently considered borderline for this procedure. Moreover, the analyses were validated against their experimental counterpart. The results of the analyses provided evidence of the clinical feasibility of PPVI and TAVI in selected cases. Stress and strain distribution was quantified under realistic loading conditions providing unique insight for device designers into device integrity when in-situ. The validation analyses confirmed the reliability of the results and suggested that the introduction of patient-specific models into the practice for cardiovascular interventions, using the described methods, would be clinically useful.